This invention relates to a passenger airbag assembly with a door and a chute.
A passenger airbag assembly is known from U.S. Pat. No. 6,394,485 in which on the passenger side of a vehicle an airbag is provided within the instrument panel. In order for the airbag to deploy a door is provided in the instrument panel which provides an area for deployment of the airbag. The door operates via the deploying airbag. When the airbag is activated, the airbag expands towards the doors. The airbag then contacts the inner side of the door and supplies a force to open the door. The door is opened by the airbag pressing on the inner side which applies enough force to separate the material of the door. In order for the door to open in a desired manner seams or fracture points are provided on the door. The disadvantage of this assembly is that the airbag supplies a force to the door which may cause tears in the door and further damage the deploying airbag.
An aspect of the invention is to control the expansion of the deploying airbag and suitably strengthen the door in order to reduce tears and damage to the door.
This aspect can be achieved in that an airbag door is provided with steel inserts molded as part of the passenger airbag chute assembly which defines the passenger airbag deployment area through the instrument panel.
This chute is a molded plastic part which the passenger airbag mounts to on the top surface of the instrument panel. This chute guides a cushion of the airbag out during deployment. During operation the deploying airbag may supply a force sufficient enough to damage the doors or tear or separate the doors at mounting points at the sides. The damage or stressing of the doors at the mounting points can lead to the doors being ripped off or injury to the deploying airbag. The airbag doors can comprise two separate steel pieces with three slots spaced equally apart on each part. The steel inserts provide strength to the doors. The slots reduce additional stress or strain on the material to prevent the doors from tearing or separating at the mounting parts. The slots can absorb strain on the steel inserts which may damage the door material. The chute and door can be molded as a unit. The steel inserts would then be insert molded into the unit.
A further aspect of certain preferred embodiments of the invention is to further protect the cushion of the deploying airbag and prevent large stress or strain at the hinge or mounting points of the airbag doors.
This aspect is accomplished in certain preferred embodiments of the invention by a guide or reinforcement ledge spanning across the chute which absorbs the forces of the deploying airbag rather than the doors. The ledge is provided along the top edge of the chute and the ledge acts as a reinforcement to reduce the stress or strain on the door as the airbag is deployed up through the chute. The ledge also guides the deploying airbag. The ledge can be located at two sides of the deployment area of the airbag and between the hinge of the door and the instrument panel.
In a further embodiment, ramps are arranged on the bottom surface of the reinforcement guide. The ramps incorporated into the design of the ledge makes the ledge stronger to thereby absorb the forces generated by the deploying airbag. The ramps also help in deflecting the cushion away from the top edge of the guide which can pinch the cushion.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.